1. Technical Field
The present apparatus is a disc-valve assembly with an automated sampling system for use in vessels and reactors, more particularly an automatic draining, crust breaking and sampling apparatus comprising a disc-type valve.
2. Background Information
Many chemical and pharmaceutical companies produce pharmaceutical intermediates and chemical compositions in reactors, such as glass-lined or stainless steel batch reactors. In the past, batch reactors have been drained through ball or plug valves. This often results in dead space (cavities) at the bottom of the vessel.
During and after the manufacturing process, it is necessary to periodically draw samples from the batch inside the reactor. Traditionally, samples have been drawn through manholes at the top of batch reactors. Unfortunately, this method of sampling can create environmental, safety and contamination problems. For example, chemical leaks or fumes can be released when gases or liquids escape from a reactor manhole which has just been opened. Also, opening the manhole and reaching into the reactor to draw a sample poses a safety risk for the industrial worker. Lastly, the batch can become contaminated or the manufacturing run can be adversely affected when the operator opens the manhole and takes a sample.
The apparatus of the present invention includes a disc-type valve. With the present valve assembly with automatic sampling system, the problem of cavities at the bottom of the reactor does not arise. With this apparatus, any crusts which have formed at the bottom of the reactor during draining can be broken. The present valve assembly also includes an automated sampling system, which eliminates the problems associated with the old manhole method of sampling a batch.
The apparatus of the present invention can be used for crust breaking, sampling, and draining of batch reactors and the like. It has four positions that can be employed by the batch operator as desired: 1) open position for draining the reactor, 2) closed position for shutting off the opening between the apparatus and the reactor, 3) crust breaking position for breaking any crusts which may have formed at the bottom of the reactor, and 4) sampling position for taking a small sample of the media. The present invention frees the operator for other tasks because it is automated. In addition, the valve of the present invention has a smooth bore so that the liquids in the reactor flow smoothly through the central channel with minimal interruption.